U.S. Change in Total Generation Capacity Jan-2011 to Dec-2015

Every month the US Federal Energy Regulatory Commission (FERC) publishes its 'Energy Infrastructure Update' which contains details on new, nationwide, capacity additions as well as total installed generation capacity. The difference between total installed generating capacity in January 2011 and December 2015 is shown;

This analysis reveals the dramatic shift which has been taking place over the last few years. In short: massive reductions in traditional generation types - specifically coal and oil - and equally large increases in non-traditional generators (wind and solar) as well as the more traditional natural gas.

Solar significantly understated. Since the FERC solar number only includes installations in excess of 1 megawatt of capacity it is likely that it excludes almost all commercial scale installations and certainly all residential solar. In other words it significantly understates the total. To get an indication of the amount: consider that FERC estimated 2015 solar installations of 2.6 GW (thousand megawatts) whereas the Solar Energy Industries Association (SEIA) put the figure at 7.3 GW. Alternatively - where FERC estimated total solar additions of 13.3 GW from January 2011 to December 2015, SEIA put the figure at 23.6 GW.